Table of symbols for metals, chemicals and compounds used in Johann Joachim Becher's (1635-1682) portable furnace, including gold, urine, salt, arsenic and sulphur. Illustration from Becher's 'Tripus Hermeticus Fatidicus' ('The Prophetical Hermetic Tripod'), published in Frankfurt in 1689. Becher is not only famous in the history of chemistry for his theory of combustion but is notable as a technologist, miner, metallurgist and he proposed many economic schemes. He travelled much, spending a year in Cornwall, studying its mines and writing this book. He was the author of a number of books both practical and symbolic and was equally an alchemist and a chemist. Despite its arcane title, this book contains much practical chemistry and mineralogy.
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